Socket for electric jack plugs



Jan. 18, 1966 A. GREASLEY SOCKET FOR ELECTRIC JACK PLUGS Filed Dec. 18, 1963 3' 5 2' F l F g I (9 I I {7 t I I y 4 F 1 E I 'l y a Pd 9 INVE N TOR EI'IL Arlhur GR EASLEY United States Patent 3,230,497 SOCKET FQR ELECTRIC JACK PLUGS Eric Arthur Greasley, Stapleford, England, assignor to Pressac Limited, Long Eaton, England, a British company Filed Dec. 18, 1963, Ser. No. 331,610 3 Claims. (Cl. 339176) The present invention relates to an improved socket for receiving what is termed a jack plug, that is a plug in which the pin (which is inserted in the socket) is divided transversely to its length into two co-axial contact making portions which are insulated one from the other.

Broadly, according to the present invention there is pro- Wided a socket for a jack plug which comprises a hollow unitary body part which is a molding of insulating material which is formed on its inner face with two or more axially directed channels for slidingly receiving contact strips, an externally threaded bush at one end of said moulding for facilitating fixing of the socket to a support or panel and which constitutes an entry opening for the pin of a jack plug, and a cap slidable over said moulding and formed with an end wall having openings through which ends of the contact strips may project for connecting them in an electric circuit.

The assembly of the component parts of a socket as set forth in the preceding paragraph is extremely simple as it is only necessary to slide the contact strips into their associated channels or grooves whereby they are retained in spaced apart relation, and then to slide the cap over the body part until the outer ends of the strips engage through the openings to leave outer portions of the strips exposed for connection in a required circuit.

As the strips are enclosed in the body part and not exposed there is no risk of them becoming distorted, and as they are positively located in the said grooves there is no risk of a short circuit.

To enable the invention to be clearly understood, a preferred embodiment thereof will now be described by way of example with reference to the accompanying drawings, wherein:

FIGURE 1 illustrates a socket of a first embodiment in elevation.

FIGURE 2 is a vertical section.

FIGURE 3 is a transverse section taken on the line IIIIII of FIGURE 1.

FIGURE 4 illustrates the three contact strips in perspective.

FIGURE 5 illustrates a socket of a second embodiment in elevation, and

FIGURE 6 is a vertical section through the socket shown in FIGURE 5.

Referring firstly to FIGURES 1 to 4 of the drawings, the socket comprises a one-piece tubular molded body part 1 of a suitable plastics material which is formed integrally at one end with an externally threaded smaller diameter hollow boss or bush 2 for receiving a nut 3 by means of which the socket may be secured to a support or panel. The mouth of this boss constitutes an entry opening for guiding the pin of a jack plug into the cavity of the body part 1.

In the embodiment being described the body part 1 is fitted with three contact strips or fingers (as shown in FIGURE 4) and for this reason has its inner face formed with three parallel channels or grooves 4 which extend longitudinally or axially of the body part.

The first contact 5 is bent at one end 5a so that when it is slid into the body part the bent end 5a enters the said boss 2 as clearly shown in FIGURE 2, the bent end engaging over the step where the smaller diameter boss 2 merges into said body part 1. This bent end So co-acts with and contacts the outer coaxial contact making por 3,230,497 Patented Jan. 1-8, 1966 tion of the pin of a jack plug. The other end 5b forms a solder tag.

The second contact strip 6 is shorter than the first contact strip 5 so that it does not project into the boss 2 and comprises a narrow portion 6a forming a tag and a wider portion 6b, the latter being intended to be engaged by a third contact strip 7 about to be described.

This third contact strip 7 comprises a main part 7a which engages in its associated groove in the body part 1 and one end 7c is bent back V-fashion and the end of this bent back portion is bent laterally at 7d so as to bridge the inside of the body member 1 and make contact with said second contact strip 6 until such time as the jack plug is inserted when it makes contact with the outer end or extremity of the pin of the jack plug. The end 7e forrns a solder tag. Preferably, this third contact strip 7 is made of a hard springy material such as Phosphor bronze or beryllium-copper.

The fitment of the strips 5, 6 and 7 in the channels or grooves 4 ensures that they are positively located and that the parts in said grooves are insulated from one another.

After the inner portions of the strips 5, 6 and 7 have been slid into their respective grooves 4 in the body part 1 an outer cap or sleeve 8, closed at one end 811, is slid axially completely over the body part 1, the closed end wall 8a of this sleeve 8 being formed with very small slitl-ike openings 9 through which the tag ends of the strips 5, 6 and 7 can pass to the outside of the cap 8 to provide exposed portions which can be connected in an electric circuit.

The parts 512, 6a and 7c of the strips or fingers 5, 6 and 7 which extend through the slit-like openings 9 in the end wall 8a of the cap 8 are narrower than the main portions of the strips so that the wider main parts present shoulders which abut the inner face of the cap and so prevent axial displacement of the strips through the slits 9 in the cap.

To ensure that the cap is correctly located so that the slits 9 therein register with the ends 5b, 6a and 7e of the strips when the cap 8 is slid onto the body part 1, the body part is formed (see FIGURE 3) with a longitudinal groove 10 on its outer face in which can slide a rib 11 formed integrally with and internally of the cap 8 so that unless the rib 11 and groove 10 are aligned the cap cannot be pushed over the body part. Alternatively, the groove 10 can be formed inside the cap 8 and the rib 11 on the outside of the body part 1.

Referring next to the modification illustrated by FIG- URES 5 and 6, the construction is very similar to that illustrated by FIGURES 1 to 4 except for minor details. In this embodiment the cap or sleeve 8 is made more shallow and only extends for approximately half the length of the body part 1 and the surface of the latter left exposed by the cap 8 is formed with circumferential ribs 12 to facilitate handling. Also, the fixing nut 3 is serrated and formed with a screw-driver slot.

I claim:

1. A socket for an electric jack plug comprising in combination:

(a) a unitary hollow body of insulating material having an axis,

(1) an inner wall of said body defining a chamber open in both axial directions,

(2) said inner wall being formed with a plurality of axially elongated grooves, open in one axial direciton;

(b) guide means on said body for guiding a portion of a jack plug into one open axial end of said chamber, said guide means including a tubular externally threaded bush integral with said body;

(c) a plurality of contact strips, each of said strips having an inner elongated portion receivedin one of said grooves in sliding engagement and an elongated tag portion projecting from the other open axial end of said chamber, said tag portion being narrower than said inner portion and defining a shoulder with said inner portion; and

(d)' a cap member closing said other open end, said cap member being formed with a'plurality of slits there through,- the tag portions of said contact strips respectively passing through said slits, and said shoulders thereof abutting against said cap member in said chamber,

(1) said inner wall having a radially extending face near said one open end abuttingly engaging one of said inner portions.

2. A socket as set forth in claim 1, wherein the said inner portions of said contact strips'are-in abutting radial contact with said inner wall of saidunitary hollow body insaid grooves.

- 3; For assembly into a socket for a jack plug, in combination:

(a) a unitary hollow body of insulating material having an axis,

(1) an inner wall of said body defining a chamber having a first and a second axially terminal opening, said second opening being larger than said firstopening,

(2) said inner wall-being formed with a plurality of grooves axially extending inward from said second opening and having respective axially closed ends in said chamber;

(b) a tubular guide member integral with said body extending from said first opening outward of said chamber;

(0) a plurality of contact strips, each contact strip having an elongated inner portion and a tag portion longitudinally extending from said inner portion and narrower than the same so as to define a shoulder therewith, the inner portion of each contact strip being dimensioned to be slidably received in a respective oneof said grooves in abutting engagement with said closed end while the tag portion projects outward from said second opening; and

(d) a cap member adapted conformingly to receive a portion of said body in a position in which a portion of the cap member closes said second opening, said cap member being formed with a plurality of slits therethrougli for passage of said tag portions in said position of said body when the corresponding inner portions are received in said grooves.

References Cited by the Examiner UNITED STATES PATENTS 2,444,048 6/1948 Keller 339-193 2,717,367 9/1955 Puerner 339-185 2,722,670 11/1955 Oliver 339-183 2,923,912 2/1960 Benander 339-210 3,027,537 3/1962 Hess et a1 339-217 X 3,108,843 10/1963 Prantz 339--183 X 3,128,050 4/1964 Parker 339126 X 30 JOSEPH D. SEERS, Primary Examiner.

W. DONALD MILLER, Examiner. 

1. A SOCKET FOR AN ELECTRIC JACK PLUG COMPRISING IN COMBINATION: (A) A UNITARY HOLLOW BODY OF INSULATING MATERIAL HAVING AN AXIS, (1) AN INNER WALL OF SAID BODY DEFINING A CHAMBER OPEN IN BOTH AXIAL DIRECTIONS, (2) SAID INNER WALL BEING FORMED WITH A PLURALITY OF AXIALLY ELONGATED GROOVES, OPEN IN ONE AXIAL DIRECTION; (B) GUIDE MEANS ON SAID BODY FOR GUIDING A PORTION OF A JACK PLUG ONE OPEN AXIAL END OF SAID CHAMBER, SAID GUIDE MEANS INCLUDING A TUBULAR EXTERNALLY THREADED BUSH INTEGRAL WITH SAID BODY; (C) A PLURALITY OF CONTACT STRIPS, EACH OF SAID STRIPS HAVING IN AN INNER ELONGATED PORTION RECEIVED IN ONE OF SAID GROOVES IN SLIDING ENGAGEMENT AND AN ELONGATED TAG PORTION PROJECTING FROM THE OUTER AXIAL END OF SAID CHAMBER, SAID TAG PORTION BEING NARROWER THAN 